名校
解题方法
1 . 已知
为正项等比数列,
是它的前
项和,若
,且
与
的等差中项为
,则
的值是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f64d5b1d831630334e494c39d0343872.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daf464629fa321a6ff7401ab79f07083.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7fd71bc7e6668f90f259ad0b06dd60c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4700efcb84c4027ce7a50af0d5212fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d27182444d3da4003680f07ec299087c.png)
A.29 | B.30 | C.31 | D.32 |
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2016-12-04更新
|
1008次组卷
|
7卷引用:【全国百强校】吉林省长春市实验中学2019届高三上学期开学考试数学(理)试题
名校
2 . 在
中,角A、B、C的对边分别为a、b、c,面积为S,已知![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ab46f5c3a111557d38c49e10fa99388.png)
(Ⅰ)求证:
成等差数列;
(Ⅱ)若
求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd936a2405709574af0a73543d94ad9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ab46f5c3a111557d38c49e10fa99388.png)
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bbf5887ebf0a2fb425dc594bb983585.png)
(Ⅱ)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f98ebc95098f1b6eae7b34ed429aa60d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
您最近一年使用:0次
2016-12-03更新
|
1413次组卷
|
5卷引用:2020届吉林省长春市第十一高中高三下学期线上模拟考试数学(理)试题
11-12高三下·吉林长春·开学考试
3 . 在数列
中,
,
为常数,
,且
,
,
成公比不为1的等比数列.
(1)求
的值;
(2)设数列
的前
项和为
,试比较
与
的大小,并说明理由.
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777179717632/1570777185107968/STEM/101d9029853b4eb5b4c428bbefb5f044.png)
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777179717632/1570777185107968/STEM/7244d261f22d464dbcfc05305b697c08.png)
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777179717632/1570777185107968/STEM/dc263f95fc9a40c18323419540759410.png)
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777179717632/1570777185107968/STEM/cc0b7edc6bdc42f096c4a0c1ab123ea0.png)
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777179717632/1570777185107968/STEM/b11bbc11b5b94752bfccb9889a7c159b.png)
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777179717632/1570777185107968/STEM/45a5f7aae855417cb27b5cce0eb670f8.png)
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777179717632/1570777185107968/STEM/1e64f717707247f2ad6b8565ac71f30c.png)
(1)求
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777179717632/1570777185107968/STEM/c95ed8373ab94310add7cf1cc9d1516b.png)
(2)设数列
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777179717632/1570777185107968/STEM/101d9029853b4eb5b4c428bbefb5f044.png)
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777179717632/1570777185107968/STEM/772a160bacff41db8dcf98c782603a3b.png)
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777179717632/1570777185107968/STEM/bbec8a413fdb45b19efb196acf8baef9.png)
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777179717632/1570777185107968/STEM/bbec8a413fdb45b19efb196acf8baef9.png)
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777179717632/1570777185107968/STEM/d3028826ea9349d7bfeaad8d5b8bc3a5.png)
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4 . 已知矩形ABCD的边长
,一块三角板
PBD的边
,且
,如图.
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777179717632/1570777185067008/STEM/fd0b99f6b01b4b9892b14f5852f263ff.png?resizew=191)
(1)要使三角板
PBD能与平面ABCD垂直放置,求
的长;
(2)求四棱锥
的体积
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c867c63f7120a8d263f2b13704b991e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6595597d25112f247753397d25bf5080.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff3a94038e3ce9ef000eadaea8330343.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45a87e5cfaf3a816f75f84a204ebaeee.png)
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777179717632/1570777185067008/STEM/fd0b99f6b01b4b9892b14f5852f263ff.png?resizew=191)
(1)要使三角板
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6595597d25112f247753397d25bf5080.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e57c75b6862f6f0325e2f4aa8b279fd.png)
(2)求四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d02bd5cfe804460846423e77f72db10f.png)
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11-12高三下·吉林长春·开学考试
5 . 数列{an}是公差不为0的等差数列,其前n项和为Sn,且S9=135,a3,a4,a12成等比数列.
(Ⅰ)求{an}的通项公式;
(Ⅱ)是否存在正整数m,使
仍为数列{an}中的一项?若存在,求出满足要求的所有正整数m;若不存在,说明理由.
(Ⅰ)求{an}的通项公式;
(Ⅱ)是否存在正整数m,使
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6690fb50cda2d223245c0cfc36a1373f.png)
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11-12高三下·吉林长春·开学考试
6 . 某人站在60米高的楼顶A处测量不可到达的电视塔高,测得塔顶C的仰角为300,塔底B的俯角为150,已知楼底部D和电视塔的底部B在同一水平面上,则电视塔的高
为______________ 米.
为
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